1. Field of the Invention
The present invention relates to a microwave oven, and more particularly, to a uniform heating structure for a microwave oven which is capable of distributing microwaves generated by a magnetron more uniformly throughout the food being cooked in a cavity.
2. Description of the Background Art
Generally, a microwave oven is an apparatus for generating microwaves and cooking food by the microwaves.
Hereinafter, the structure and operation of a conventional microwave oven will be described.
As illustrated in FIG. 1, the microwave oven includes a casing(F) having a cavity 10 for cooking food therein at its center portion and an electric chamber 20 for generating microwaves at one side of the cavity 10, and a door 70 hingeably connected to one side of the casing(F) and opening and closing the cavity 10.
In detail, the cavity 10 includes a turntable 30 mounted on the bottom surface 11 of the cavity 10, and a turntable motor(not shown) for rotating the turntable 30.
And, as illustrated in FIG. 2, the electric chamber 20 includes a magnetron 40 for generating microwaves, a wave guide 50 for guiding the microwaves generated by the magnetron 40 to be radiated to the cavity 10, a pair of openings 60 for converting the microwaves radiated from the wave guide 50 into circular polarized waves, and a high voltage converter(not shown) for supplying power to the magnetron.
The cavity 10 of the conventional microwave oven is formed to have a rectangular space. The sections of the openings 60 and wave guide 50 protecting the openings 60 which are provided at one side wall 12 of the cavity 10 are formed in a square. The square sections of the wave guide 50 and openings 60 are disposed in the same horizontal and vertical direction as the one side wall of the cavity to which the wave guide 50 and openings 60 are connected.
Hereinafter, the operation of the microwave oven will be explained.
When a user places food on the turntable 30 of the cavity 10, and then applies power, the magnetron 40 generates microwaves, said microwaves being guided by the wave guide 50 to thus be radiated to the cavity 10 through the openings 60. The food is heated by the microwaves radiated to the cavity 10, and the turntable 30 is rotated by the turntable motor for uniform cooking performance.
Meanwhile, the essential point of cooking food by means of the microwave oven is how uniformly the microwaves generated by the magnetron are distributed to the food.
However, in the above-described rectangular-shaped structure for the cavity 10 of the conventional microwave oven, parts of the microwaves generated by the magnetron 40 are directly delivered to the food on the cavity 10 in the process in which the microwaves generated by the magnetron 40 are radiated to the cavity 10 through the wave guide 50 and the openings 60. In addition, most of the microwaves are randomly reflected to an interior wall of the rectangular-shaped cavity 10, thus causing an unpredictable distribution of the microwaves.
FIG. 3 is a view illustrating the distribution of microwaves generated in the cavity 10 of the conventional microwave oven. In FIG. 3, with respect to the strength of microwaves by colors, black indicates strong, gray indicates intermediate, and white indicates weak.
Therefore, the rectangular-shaped structure for the cavity 10 of the conventional microwave oven has a problem that xe2x80x98uniform portionsxe2x80x99 and xe2x80x98non-uniform portionsxe2x80x99 are formed while cooking food, which degrading the cooking performance of the microwave oven.
Accordingly, it is an object of the present invention to provide a uniform heating structure for a microwave oven which is capable of distributing microwaves generated by a magnetron more uniformly throughout the food being cooked in a cavity.
To achieve the above object, there is provided a uniform heating structure for a microwave oven according to the present invention, which includes: a magnetron for generating microwaves; a wave guide for guiding the microwaves generated by the magnetron; a pair of openings for radiating the microwaves guided by the wave guide in the form of circular polarized waves; and a cavity which is shaped in a polyhedron more than a rectangular and in which more than one interior walls constructing the polyhedron slope at a predetermined angle with respect to a neighboring interior wall.
Additional advantages, objects and features of the invention will become more apparent from the description which follows.